Al(OH)_3和α-SiO_2对聚磷酸铵热分解过程的影响

Effect of Aluminium Hydroxide and α-SiO_2 on Thermal Decomposition of Ammonium Polyphosphate

采用热质量损失分析和X射线衍射分析考察了Al(OH)3和α-SiO2对聚磷酸铵(APP)热分解过程的影响,探讨了APP高温热分解行为及其与添加相之间的相互作用。结果表明,APP和Al(OH)3混合物中,APP的分解产物多聚磷酸和Al(OH)3的分解产物反应生成AlNH4HP3O10,加速了APP热分解,两者初始相互反应温度提前至263℃,600~900℃生成稳定的Al(PO3)3;APP和α-SiO2混合物初始热分解温度与APP的第1阶段分解温度一致,450℃时,APP热分解产物与α-SiO2反应已生成SiP2O7。Al(OH)3和α-SiO2共同添加与它们分别添加对APP热分解的影响有较大区别:APP、Al(OH)3和α-SiO2混合物的初始相互反应温度进一步降低至261℃,Al(OH)3的热分解产物优先与APP热分解产物发生反应,生成AlNH4HP3O10。α-SiO2促进了AlNH4HP3O10发生分解生成Al2P6O18,抑制了Al2P6O18转化为Al(PO3)3,600~900℃时,残留物有α-SiO2、Al(PO3)3以及Al2P6O18。

The influence of aluminium hydroxide and α-SiO2 added into ammonium polyphosphate(APP) on the thermal decomposition behavior of APP was investigated.The interaction with phases additions was analyzed by thermogravimetric analysis and X-ray powder diffraction,respectively.The polyphosphoric acid,which are the decomposition products of APP,can react with the decomposition products of Al(OH)3 to generate AlNH4HP3O10 at 263 ℃,and Al(PO3)3 after 600 ℃.The initial decomposition temperature of APP and α-SiO2 compound is as the same as that of APP unanimously.The decomposition products of APP can react with α-SiO2 to generate Si P2O7 at 450 ℃.The influence of aluminium hydroxide and α-SiO2 is different from that of aluminium hydroxide or α-SiO2 on the thermal decomposition behavior of APP.The initial decomposition temperature of APP,Al(OH)3 and α-SiO2 compound further decreases to 261 ℃.The APP can react with the thermal decomposition product of Al(OH)3 to produce AlNH4HP3O10,and Al(PO3)3,Al2P6O18 and α-SiO2 at 600–900 ℃.α-SiO2 can promote the thermal decomposition of AlNH4HP3O10 to Al2P6O18 and inhibit the conversion of Al2P6O18 to Al(PO3)3.